In the conventional flowerpots, water is put over the surface of the soil directly, and therefore, the water remains in the pot for a short period of time. If there is an excess water put into the pot, it is drained away through the drain hole in the bottom of the flower pot. Accordingly regardless of whether a large amount or small amount of water is put into the flower pot, the water can remain in the pot for only a short period of time, and therefore, there arises the troublesome problem of putting the water into the pot every day or every several days. Not only so, but if the caring person is absent because of a trip or other reasons, the plant in the pot can die due to the water deficiency. Further, in the summer season, the surface soil appears dry in spite of the fact that the water is profusely contained within the soil. In such a case, if the water is put too frequently, the roots of the plant can be caused to become rotten due to the excess water.